The Ultimate Sacrifice is an extremely patriotic & heroic devotion to one's country, particularly in the United States of America. The Ultimate Sacrifice is what you make of it, but generally it is on an extreme level, exceeding that of death.

"If you want the definition of patriotism & an example of the Ultimate Sacrifice, play Metal Gear Solid 3 : Snake Eater."
-me

This is the ability to be willing to do give up all you have to show you love your one true love. . .This doesnt mean to give up going after them it means the ability to chase her around the world and let her realize you need her more than anything else. ..

John just to show how much he loved Elizabeth was willing to have the ultimate sacrifice for her and stopped everything and joined the army to be able to make her dreams come true if she gave you a chance again